In a roof support of the aforementioned kind, it is known to provide gap seals in the form of L-shaped plates on the roof cap and goaf shield. These plates are usually flexibly adjustable laterally of the support so that the side walls thereof engage side walls of similar plates on adjacent roof supports to seal off the gaps between the caps and goaf shields to provide a screen between the working or access zone and the stowage or rubble zone of the mine working. German Patent Specification No P28 53 050 describes such an arrangement. In the region where the goaf shield of the support meets the roof cap the side walls of the gap sealing plates overlap one another and it is known to interconnect the overlapping walls with pivot joints to permit the gap sealing plates to follow pivotable movements between the shield and the roof cap. Hitherto these pivot joints have been detachably secured in position with the aid of locking plates fixed in position with screws. The accessibility of the screws is poor and the screws are prone to become jammed with rust, especially in the harsh environment in a typical mine working.
A general object of the present invention is to provide an improved pivot connection for the overlapping side walls of the gap seal of a roof support.